The QBitArray class provides an array of bits. More...
#include <qbitarray.h>
Inherits QByteArray.
QString inherits QByteArray, which is defined as QArray<char>.
Since QBitArray is a QArray, it uses explicit sharing with a reference count.
A QBitArray is a special byte array that can access individual bits and perform bit-operations (AND, OR, XOR and NOT) on entire arrays or bits.
Bits can be manipulated by the setBit() and clearBit() functions, but it is also possible to use the indexing [] operator to test and set individual bits. The [] operator is a little slower than the others, because some tricks are required to implement single-bit assignments.
Example:
QBitArray a(3);
a.setBit( 0 );
a.clearBit( 1 );
a.setBit( 2 ); // a = [1 0 1]
QBitArray b(3);
b[0] = 1;
b[1] = 1;
b[2] = 0; // b = [1 1 0]
QBitArray c;
c = ~a & b; // c = [0 1 0]
Constructs an empty bit array.
Constructs a shallow copy of a.
Constructs a bit array of size bits. The bits are uninitialized.
Returns the value (0 or 1) of the bit at position index.
See also: operator[].
Clears the bit at position index (sets it to 0).
See also: setBit() and toggleBit().
Returns a deep copy of the bit array.
See also: detach().
Detaches from shared bit array data and makes sure that this bit array is the only one referring the data.
If multiple bit arrays share common data, this bit array dereferences the data and gets a copy of the data. Nothing will be done if there is just a single reference.
See also: copy().
Fills the bit array with v (1's if v is TRUE, or 0's if v is FALSE).
Will resize the bit array to size bits if size is nonnegative.
Returns FALSE if a nonnegative size was specified and if the bit array could not be resized, otherwise returns TRUE.
See also: resize().
Performs the AND operation between all bits in this bit array and a. Returns a reference to this bit array.
The two bit arrays must have the same size. The debug library will warn you if they aren't, the production library blithely ignores the problem.
Example:
QBitArray a(3), b(3);
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b[0] = 0; b[1] = 0; b[2] = 1; // b = [0 0 1]
a &= b; // a = [0 0 1]
See also: operator|=(), operator^=() and operator~().
Assigns a shallow copy of a to this bit array and returns a reference to this array.
Implements the [] operator for bit arrays.
The returned QBitVal is a context object. It makes it possible to get and set a single bit value.
Example:
QBitArray a( 3 );
a[0] = 0;
a[1] = 1;
a[2] = a[0] ^ a[1];
The functions testBit(), setBit() and clearBit() are faster.
See also: at().
Performs the XOR operation between all bits in this bit array and a. Returns a reference to this bit array.
The two bit arrays must have the same size. The debug library will warn you if they aren't, the production library blithely ignores the problem.
Example:
QBitArray a(3), b(3);
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b[0] = 0; b[1] = 0; b[2] = 1; // b = [0 0 1]
a ^= b; // a = [1 0 0]
See also: operator&=(), operator|=() and operator~().
Performs the OR operation between all bits in this bit array and a. Returns a reference to this bit array.
The two bit arrays must have the same size. The debug library will warn you if they aren't, the production library blithely ignores the problem.
Example:
QBitArray a(3), b(3);
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
b[0] = 0; b[1] = 0; b[2] = 1; // b = [0 0 1]
a |= b; // a = [1 0 1]
See also: operator&=(), operator^=() and operator~().
Returns a bit array which contains the inverted bits of this bit array.
Example:
QBitArray a(3);
a[0] = 1; a[1] = 0; a[2] = 1; // a = [1 0 1]
QBitArray b = ~a; // b = [0 1 0]
Resizes the bit array to size bits. Returns TRUE if the bit array could be resized.
When expanding the bit array, the new bits will be uninitialized.
See also: size().
Sets the bit at position index (sets it to 1).
See also: clearBit() and toggleBit().
Sets the bit at position index to value.
Equivalent to:
if ( value )
setBit( index );
else
clearBit( index );
See also: clearBit() and toggleBit().
Returns the size (number of bits) of the bit array.
See also: resize().
Returns TRUE if the bit at position index is set.
See also: setBit() and clearBit().
Toggles the bit at position index.
If the previous value was 0, the new value will be 1. If the previous value was 1, the new value will be 0.
See also: setBit() and clearBit().
Returns the XOR result between the bit arrays a1 and a2.
See also: QBitArray::operator^().
Returns the AND result between the bit arrays a1 and a2.
See also: QBitArray::operator&=().
Writes a bit array to a stream.
Serialization format:
Returns the OR result between the bit arrays a1 and a2.
See also: QBitArray::operator|=().
Reads a bit array from a stream.
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